高温下含缺陷CL-20初始化学反应的分子动力学模拟

To study the influence of crystal defects on the initial reaction of hexanitrohexaazaisowurtzitane (CL-20), molecular dynamic simulation and ReaxFF-lg reactive force field are used to study the initial reaction path, thermal decomposition products, and reaction kinetics of CL-20 with vacancy defects at high temperature (1500-3500 K). The results show that the initial decomposition path of CL-20 with vacancy is the breaking of N─NO₂ bond, the same as that of perfect crystal. The vacancy defects prove to increase the frequency of ring-opening reactions and the production of NO₂. Compared with perfect CL-20, it can be seen that the vacancy defects would reduce the CL-20 activation energy barrier and accelerate its thermal decomposition process. The reaction rate constants of CL-20 with 16.7% vacancies are 1.7 and 1.4 times higher than that of perfect CL-20 at 2000 K and 3000 K, respectively. The CL-20 molecules around the vacancy are easier to decompose, leading to the increase of the sensitivity of CL-20.